1. Field of the Invention
The present disclosure relates generally to downhole tools such as drill bits useful in operations related to oil and gas exploration, drilling and production. More particularly, embodiments of the disclosure relate to drill bits including both fixed and rotational cutting elements thereon.
2. Background
Often in operations for the exploration, drilling and production of hydrocarbons, water, geothermal energy or other subterranean resources, a rotary drill bit is used to form a wellbore through a geologic formation. Rotary drill bits may generally be classified as either fixed-cutter drill bits with stationary cutting elements, or roller-cone drill bits with cutting elements mounted on one or more roller cones that are mounted for rotation with respect to a bit body of the drill bit.
Fixed-cutter drill bits are often referred to as “drag bits” and may be constructed with a plurality of fixed cutting elements mounted to the bit body. The bit body for a fixed-cutter drill bit may be constructed of a metallic material such as steel or a matrix material formed by infiltrating a reinforcement material with a molten binder. The fixed cutting elements can be affixed to an outer profile of the bit body such that hard surfaces on the cutting elements are exposed to the geologic formation when forming a wellbore. The cutting elements generally operate to remove material from the geologic formation, typically by shearing formation materials as the drill bit rotates within the wellbore.
Roller-cone drill bits may be constructed of one or more roller cones rotatably mounted to the bit body, wherein cutting elements are disposed on the roller cones. The roller cones roll along the bottom of a wellbore as the roller-cone drill bit is rotated. The cutting elements on the roller cones generally operate to remove material form the geologic material from the geologic formation, typically by crushing, gouging and/or scraping material from the geologic formation to drill the wellbore.
Hybrid drill bits have been developed with features of both fixed-cutter and roller-cone drill bits for various purposes. For example, in some instances, a hybrid drill bit may be more durable, thereby permitting greater depths to be drilled before requiring maintenance or replacement of the drill bit than either a fixed-cutter drill bit or roller-cone drill bit alone.